Two weeks later the snow was gone again. At least, gone from all of central Maine except our house in Troy, where before Friday’s rainsnow there was still an icy crust under the firs and spruces.

As noted here before, it has snowed this winter, but the catch has been that immediately afterward it gets so warm the snow disappears. It’s unusual for this to happen so completely so frequently in these parts. No one knows whether this particular mild January is telling us anything about global warming (as it used to be called until too many people were incapable of understanding what the phrase means and the descriptor was tweaked to “climate change”), but it sure seems likely to be part of a trend to overall warmer weather which has been under way for some time now.

Several readers, with helpful intentions I’m sure, reassured me earlier this month with a few pats on the head that climate change, if it’s even happening, is a natural occurrence that’s nothing to do with us and moreover, to jog me out of naivete, that global warming is a hoax. Don’t worry, be happy, we were sagely advised in the 1980s.

Here are some of the points I’ve heard that are meant to reassure me there’s no need to worry about climate change or global warming:

• It still gets cold in winter.

• Earth’s climate has always changed and always will change.

• Global warming is just a theory.

• There is no proof the exhaust from my car hurts anything.

• Scientists are often wrong.

• Scientists fake climate research findings.

• Global warming is not mentioned in the Bible.

• There was no Y2K disaster.

The problem I have with these arguments is that I believe in the existence of computers, cellphones, penicillin, bone marrow transplants and internal combustion engines. I also believe in photosynthesis, DNA, infrared light, blood types, viruses, the theory of relativity and the vibration A440, even though I have never seen any of these actual items or processes with my eyes.

What I mean by this is that the same method of study — namely, what we call “the scientific method” — led to microchips, life-saving chemistry, instant communication and so on. So that method has a certain high reliability. It has been applied to Earth’s climate, and so the findings of climatologists are very likely to be in the same range of reliability.

Now, if the climatologists were disagreeing about the findings, then we would have a situation where the research was incomplete, the matter was not fully understood and global warming would be “just a theory.” In other words, the scientists would not yet be sure whether the proposed explanation was completely accurate to reality or not. Scientists are often wrong about their theories. That’s why they keep compiling, analyzing and checking data until they agree on an accurate explanation.

When they agree, a theory is no longer a theory but a fact. In the case of global warming, the vast majority of tens of thousands of climate scientists agree that the Earth’s climate overall is warming. For all intents and purposes, global warming is not a theory, but a fact.

Global surface temperatures have been rising fairly steadily since about 1900 — which is to say, around the time our greenhouse-gas-producing activities kicked into high gear. According to the National Oceanic and Atmospheric Association, the decade 2001 through 2011 included the first, fourth, fifth, sixth, seventh, ninth, 10th and 11th warmest years since records started being kept in 1880; 2005 and 2010 tie for the warmest years ever. The coolest, 2008, was still the 13th warmest year out of the last 131.

Whether the warming will continue to increase, and how severe its effects will be, is still debated. There is something like a consensus among scientists that the warming will increase, though some think it may have topped out in the last 10 years. Many agree the effects of warming are likely to be dire — taking the form of melting glaciers (vanishing water supplies), increases in extreme weather (severe hurricanes, tornadoes and floods) and droughts (famine in East Africa), all events that are seen to be increasing recently — but there is not complete agreement on this. So we can’t call these “facts,” but predictions based on the analysis of extensive data. Which is science’s fundamental goal and method.

The causes of the warming, by most scientific accounts, include human activities. A minority say that contribution is negligible, so the causes of global warming are not yet well enough understood to be called “factual.” NOAA, though, expresses the predominant scientific view: “It is important to remember both that the greenhouse effect occurs naturally, and that it has been intensified by humankind’s input of greenhouse gases into the atmosphere.”

These conclusions were not drawn from glancing over a few Wikipedia articles once or twice, like a horse racing sheet, and a winning theory picked. Global warming is not a hasty prediction based on a poorly understood or remote statistical possibility, like the Y2K scare or like the minuscule possibility that the detonation of a nuclear weapon could trigger the sudden combustion of the whole atmosphere. It is not based on a few glances at the thermometer on the window sill. Conclusions about warming result from tens of thousands of climate scientists compiling and analyzing information in minute detail for decades, all checking and rechecking each other’s work all the time. It is still being checked. You have to ask yourself, based on a general knowledge of human nature, how this many people could have kept a hoax on this scale a secret for this long.

The fact that some findings were, or may have been, faked does not imply that all the findings were faked. It’s like saying that since one student cheated on a test, therefore all students cheat on tests. Not only is it illogical, it’s ridiculous.

And for those who state that they do not believe in anything that is not mentioned in the Bible, I can only wonder what they think is happening when they use a cellphone, drive a car or take an Advil. The absence of cellphones in the Bible doesn’t mean the Bible is false. It just means there is more in heaven and Earth than is dreamt of in our philosophy, and we have found some of it out since the books of the Bible were written 2,000-plus years ago.

Global warming is a fact. It seems reasonable to think that this snow-melting January is a symptom of that fact, though I don’t know for sure and neither do the scientists because they would never draw such a conclusion that hastily. Meanwhile, it snowed on Friday so the don’t worry, be happy folks can go comfortably back to sleep. I find I am not sure what course of action, here, is noblest in the mind. The divinity that shapes our ends will hear no objections from me if this snow melts off my driveway later this week.